GHC SERIES
OM-05845
PAGE E-7
MAINTENANCE AND REPAIR
Use caution to prevent the idler assembly
from dropping off the idler pin; the idler
may be damaged if it falls on a hard sur
face.
Pull the head assembly (01A) from the housing as
sembly (04). Take care not to let the idler assembly
(02) slide off the idler pin (01AB). Remove the
check pipe plug (P) from the suction side of the
head (01AA).
Use caution when handling the idler (02A)
and the rotor shaft assembly (03A). These
parts have sharp edges which will grow
sharper with use.
NOTE
The idler bushing (02B) may be damaged during
removal. Do not remove the idler bushing unless re
placement is required.
Remove the assembled idler (02A) and idler bush
ing (02B) from the head assembly. Inspect the idler
bushing for excessive wear or scoring. If replace
ment is required, use an arbor (or hydraulic) press
to remove the idler bushing from the idler.
To remove the idler pin (01AB), lay the head as
sembly (01A) on an arbor (or hydraulic) press with
the idler pin (01AB) facing down and press the idler
pin from the head.
Seal Removal (05)
See
PUMP DISASSEMBLY
and disassemble the
pump up to and including the
Rotor Adjusting
Sleeve (07)
. As the rotor adjusting sleeve assem
bly (07A) is unscrewed from the backhead (06AA),
the seal stationary element will remain inside the
rotor adjusting sleeve.
Remove the seal stationary seat and O‐ring from
the rotor adjusting sleeve assembly.
Use caution
not to damage the stationary seat sealing face.
Remove the rotor adjusting sleeve O‐ring (07B).
With the head kit (01), idler assembly (02) and rotor
adjusting sleeve (07) removed, push the rotor/
shaft assembly (03A) toward the head end of the
pump until the seal between the shaft and rubber
bellows of the seal breaks loose. Slide the rotor/
shaft back into the housing until the rotating por
tion of the seal can be grasped. Slide the rotating
portion of the seal completely off the shaft.
Continue as required with
PUMP DISASSEMBLY
.
Rotor/Shaft Removal (03)
With the seal removed, simply slide the rotor/shaft
assembly (03A) out of the housing (04A). Due to
close machine tolerances and assembly practices,
the rotor/shaft is available only as an assembly.
Further disassembly is not required.
Backhead Kit Removal (06)
Remove the screws (B) securing the backhead as
sembly (06A) to the housing assembly (04), and
separate the assemblies. Remove and discard the
gasket (06B).
NOTE
The shaft bushing (06AE) may be damaged during
removal. Do not remove the bushing unless re
placement is required.
Use an arbor (or hydraulic) press and a suitably
sized dowel to press the shaft bushing out of the
backhead (06A).
Housing Assembly (04)
NOTE
Seal cavity pressure relief is accomplished using
socket head pipe plugs (P) in the back side of the
housing. Removal of the plugs is not required un
less the direction of pump rotation is to be
changed.
If pump rotation is to be changed, remove the
socket head pipe plugs (P) from the housing. The
hole adjacent to the discharge port will have a
